Recently, demands for high-resolution and high-quality videos, such as high-definition (HD) and ultrahigh-definition (UHD) videos, are increasing in various fields of applications. As video data has higher resolution and higher quality, the amount of data more increases relative to existing usual video data. Accordingly, when video data is transferred using media such as existing wired and wireless broad band lines or is stored in existing storage media, transfer cost and storage cost increase. In order to solve these problems occurring with an increase in resolution and quality of video data, high-efficiency video compression techniques may be utilized.
Video compression technology includes various techniques, such as an inter prediction technique of predicting pixel values included in a current picture from previous or subsequent pictures of the current picture, an intra prediction technique of predicting pixel values included in a current picture using pixel information in the current picture, and an entropy encoding technique of assigning a short code to a value with a high appearance frequency and assigning a long code to a value with a low appearance frequency. Video data may be effectively compressed and transferred or stored using such video compression techniques.